1. Technical Field
The present invention relates to a method of manufacturing an electronic device for improving a method of welding a container main body and a lid member, and an electronic apparatus and a mobile apparatus using the device.
2. Related Art
For a structure for air-tightly sealing an electronic element within a container, an electronic element is placed within a ceramic container main body with one face opened and electrical conduction is established between the electronic element and container main body side wiring using a conductive member, and then, a technique of sealing a sealing part formed in an opening peripheral edge part of the container main body and a metal lid member by seam welding (resistance welding), a technique of joining them using a laser beam or an electron beam, or the like has been used.
Patent Document 1 (JP-A-2010-178113) has disclosed a piezoelectric device manufactured using seam welding. The piezoelectric device includes a container for electronic element and a piezoelectric element. The container for the electronic element includes a container main body having a recessed part and a lid member.
In the container main body, a frame part is provided on one principal surface of a substrate part and the recessed part is formed. The substrate part forming the container main body is formed by stacking of a plurality of layers of a ceramic material such as alumina ceramics, for example. The frame part is formed using a metal such as Kovar and a seal ring in a frame shape having a hollow part is used. Further, the frame part is connected to metalization formed on the one principal surface of the substrate part by brazing or the like. Further, a pair of element mounting pads are provided on the one principal surface of the substrate part. Furthermore, a plurality of mounted terminals are provided on the other principal surface of the container main body.
The lid member is formed using a 42 Alloy, Kovar or the like, and has an inclining part with a thickness larger from the outside edge part toward the inside provided on the principal surface facing the recessed part side. The lid member is provided on the frame part of the container main body within a predetermined atmosphere, a roller electrode of a seam welding machine is brought into contact with the lid member, and the roller electrode is moved along the outer peripheral edge of the lid member while a current is flown in the roller electrode, and thereby, the lid member is joined to the frame part.
The inclining part is provided from the outside edge part toward the inside in the lid member, contact between the roller electrode and a carrier jig may be prevented. Further, by increasing the tilt angle of the roller electrode, the width of the contact (joint width) between the lid member and the frame part may also be made smaller. It is disclosed that thermal stress (residual stress) on the container main body may be reduced thereby, and cracking, chipping, or the like produced in the container main body may be prevented.
However, recently, containers have been getting smaller and smaller, and, if an inclination is formed to increase the thickness from the end edge toward the center of the lid member in the structure of the lid member as disclosed in Patent Document 1, there has been a problem that it is difficult to avoid occurrence of cracking of the container main body due to thermal stress (residual stress) generated at welding because the thickness of the lid member itself is only about 0.1 mm.